Marine Geology

Since the first marine geological research aboard the R/V "Vityaz" lead by P.LBezrukov and V.P.Zenkovich in 1949 the geological studies have been among the major ones in the complex oceanological investigations at the Institute. The Russian marine geological school founded within the Institute's walls by P.LBezrukov and his disciples and colleagues has become leading in our country and ranking high among the world's geologists, in particular, as a champion of many new ides that form the base of the Earth sciences. The geological direction of the Institute's research embraces a wide range of scientific disciplines, such as lithology, mineralogy, geochemistry and stratigraphy of bottom sediments; micropale-ontology and paleooceanology; sediment and ore formation; geology of oil and gas; geomorphology, geophysics, tectonics and geo-dynamics; geochemistry and biogeochemistry; dynamics of the shores and shelves.

The development of marine geology is associated with the names of many well-known scientists like P.LBezrukov, A.P.Lisitzin, G.B.Udintsev, S.LSolov'ev, A.A.Geodekyan, L.P.Zonenshain, L.I.Lobkovsky, A.I'.Zhuze, Kh.M.Saidova, E.A.Ostrournov, M.V.KIenova, Yu.P.Neprochnov, A.V.Zhivago, A.A.Aksenov, O.G.Sorokhtin, I.O.Murdmaa, G.N.Baturin, N.S.Skornyakova, E.A.Romankevich, Yu.A.Bogdanov, I.I.Volkov, M.S.Barash and many others. Systematic studies of the World Ocean's bottom relief are conducted at the Institute to compile and to improve bathymetric, physiographic and geomorphologic maps of the ocean. Several atlases, including the international ones, have been published; more than 100 geographic discoveries have been made. The ridges of Shirshov, and East Indian; the rises of Shatsky, Academy of Sciences, the Institute of Oceanology, Ob, Lena; the Zenkovich swell; the Vityaz trench, the seamounts of Isakov, Bogorov, Bezrukov, Petelin, Afanasiy Nikitin and many others have appeared on the world oceans maps. The World Ocean's maximum depth of 11,022 m has been measured in the Mariana Trench. The Institute's scientists were the first in our country to accept and successfully develop a new theory - the plate tectonics theory. A new concept of the two-layer plate tectonics was developed, the first tectonic maps for the former USSR territory were constructed, paleoreconstructions of the positions of the continents and oceans in the geological past were made more precise.

The Institute has undertaken studies of a natural phenomenon of which nobody knew until recently - hydrothermal activity on the ocean floor, in the rift zones of the mid-ocean ridges, and its associated ore formation. The first hydrothermal manifestations on the ocean floor were recorded by the Institute's expeditions as far back as the late 1950s when metalliferous sediments rich in iron were sampled from the crest of the East Pacific Rise. It had been long before hydrothermal sources were found by tlie foreign researchers in the Galapagos Rift zone. By the moment, systematic research into hydrothermal manifestations with the aid of "PISCES" and "MIR" submersibles have embraced many key regions in the system of the mid-ocean ridges and back-arc spreading zones. A number of new hydrothermal fields with sulphide ore manifestations and quite unusual faunal communities have been discovered.

An important achievement of the Institute's geologists is the development of theoretical bases of the process of ocean sedimentation the core of which is formed by a concept of the three major types of sedimentation zonality: climatic, circumcontinental and vertical. Originally formulated by P.L.Bezrukov in the general form the theory was corroborated and developed in the systematic studies of water and air suspended matter, as well as of river discharge and sedimentary material dispersal by sea ice and icebergs that were undertaken for the first time in the world's science. Due to joint efforts of the Institute's geologists and biologists a leading role of biogenic sedimentation in the ocean was elucidated and substantiated. A new concept was developed of pavalancheh sedimentation as an anomalously fast sediment accumulation in definite zones concentrating an essential (more than 30%) part of sedimentary matter. The powerful sedimentary strata resulting from the "avalanche" sed-imentation may potentially be oil and gas bearing. Oil and gas potentialities of various sea areas are among the problems under special study at the Institute.

The Institute leads in the studies of oceanic iron-manganese nodules and crusts, ores potential for Mn, Ni,Co, Cu and possibly for platinoids and phosphorites. The laws governing the distribution of these ore manifestations in the World Ocean were elucidated, their chemical and mineral compositions were studied in detail and original concepts of ore genesis were worked out. The concept of phosphorite formation in the upwelling zones first developed by G.N.Baturin is now generally recognized.

Micropaleontological studies are successfully carried out at the Institute. In combination with the isotopic analyses of ocean sediments that were first employed in Russia they form the basis for stratigraphic, paleooceanological, paleoecological and paleoclimatic reconstructions and, finally, for the studies of the world oceans' geological history.

Great importance is attached to geochemical and biogeochemical studies of sedimentation and diagenetic processes. Quantitative regularities in the behaviour of chemical elements, their cycles and contribution of various sources to the chemical balance of the ocean were established. Marine geophysical measurements, the first in our country, were carried out from the R/V "Vityaz" in the 1950s. At the moment, seismoacoustic, seismic, geomagnetic, electromagnetic, geothermic studies of the ocean floor are a significant part of the Institute's geological investigations. The most important achievements of the Institute' geophysicists include complex studies of a number of the key regions in the World Ocean, including the north-western part of the Pacific, the intraplate deformation zone in the Indian Ocean, potential oil and gas bearing regions in the Bering, Barents and Kaia seas. The Institute's seismoacoustic studies laid down foundations for a discovery of the large Shtockman gas condensate field called after the R/V "Professor Shtockman" who conducted the studies. The Institute's marine geologists have been progressing in the studies of sea shores and shelves, relief formation in the boundary zone, sedimentary material transport, transformation and accumulation, shore erosion, the accumulation of mineral resources (placers, building materials).

A new scientific field, geoecology of the shelf, has been created to handle with the problems pertinent to anthropogenic effects on the geological processes in the coastal zone and prevention of consequences harmful for the environment.